So, I cut the 2nd attempt at the size of 2″ by 3″, but rotated 90 degrees from the first one, on the theory that the leather was shrinking more one direction than the other.

I used the same procedure as before to carefully stitch the leather together over the form, with one exception. At each end, I used a separate piece of silk to tie a knot and hold the ends together, and then added a few stitches crossing back and forth over the tubular end, to help prevent quite so much shrinkage.

     

I soaked the case in cool water for about 1/2 hour.  I likely didn’t need more than about 5 minutes to become thoroughly soaked.  Then I tried shrinking it in 150 degree water. I saw no apparent change. So I kicked the heat up a bit, to 175 degrees.  I immersed the case, and swirled it around until I saw some shrinkage.  This was a bit more than 30 seconds.

As you can see from the photos, by stitching across the tube ends, I did prevent excessive shrinkage there.  (I’ve already removed the thread, but you can see the holes.)  However, I’ve also confirmed that the leather shrinks more one direction than the other.  I can see the form under the stitching, and originally, the leather was slightly overlapped in that area. I don’t really like this.  It’s also shrunk so tightly, I suspect I’ll have to break the form in order to remove it.

   

So, next version – cut it 2″ by 3″, but back to the original way, where the 3″ dimension will shrink more than the 2″ dimension.  I also am beginning to think that this is a excessively complex way to stitch the tube.  I don’t think period craftsmen are likely to put the effort into something that really may not make any structural/functional difference.  I’m going to try just doing a single overcast whip stitch, instead of crossing both directions, and see how that behaves.  I will still do the separate ties at the tube ends.

I will presoak the leather at least 5 minutes, use use 175 degree water, and immerse the leather for shrinkage for 30 seconds. (I’ve got a timer on my stove so I can count accurately.)

Observing how the leather shrinks, I’ve realized that I can’t “shrink” the outer case and then insert the inner liner.  I’ll need to apply hide glue to the lower part of the liner, put the outer case on it, and then dip the case (carefully) into the hot water until it shrinks up the necessary amount.  The trickiest part will be getting the cap also shrunk properly, and not be too big.  I guess I can just measure conservatively,and trim off length of the liner if necessary.

Just so you can keep up, don’t forget the other exciting installments in this saga.